1. Field of the Invention
The present invention relates to a multilayer ceramic capacitor and a method of manufacturing the same, and more particularly, to a high capacitance multilayer ceramic capacitor having excellent reliability and a method of manufacturing the same.
2. Description of the Related Art
Generally, electronic components using a ceramic material, such as a capacitor, an inductor, a piezoelectric element, a varistor, a thermistor, or the like, include a ceramic body made of a ceramic material, internal electrodes formed in the ceramic body, and external electrodes mounted on surfaces of the ceramic body so as to be connected to the internal electrodes.
Among ceramic electronic components, a multilayer ceramic capacitor is configured to include a plurality of laminated dielectric layers, internal electrodes disposed to face each other, having the dielectric layer interposed therebetween, and external electrodes electrically connected to the internal electrodes.
Multilayer ceramic capacitors have been widely used as components in mobile communications devices such as laptop computers, personal digital assistances (PDAs), mobile phones, and the like, due to advantages thereof such as a small size, high capacitance, ease of mounting, or the like.
Recently, as electronic products have been miniaturized and multi-functionalized, chip components have also tended to be miniaturized and multi-functionalized. As a result, there is a need to miniaturize multilayer ceramic capacitors and increase the capacity thereof.
In order to increase the capacitance of multilayer ceramic capacitors, methods of making the dielectric layers thin, laminating the thinned dielectric layers, and improving coverage of the internal electrodes have been considered. In addition, a method of improving an area of the internal electrodes overlapped for forming capacitance has been considered.
In general, multilayer ceramic capacitors have been manufactured as follows. First, ceramic green sheets are prepared, and a conductive paste is printed on the ceramic green sheets to form internal electrodes. The ceramic green sheets having the internal electrodes formed thereon are stacked in an amount of several tens of layers to several hundreds of layers to fabricate a ceramic multilayer body. Thereafter, the ceramic multilayer body is compressed under conditions of high temperature and high pressure, and a cutting process is performed on the ceramic multilayer body to fabricate a green chip. Next, the green chip is calcined and sintered, and external electrodes are formed thereon, and thus, the manufacturing of a multilayer ceramic capacitor is completed.
In the case of manufacturing the multilayer ceramic capacitor by the above-described manufacturing method, since it is difficult to significantly decrease a margin part of the dielectric layer on which the internal electrode is not formed, there is a limitation in increasing the overlap area of the internal electrodes. In addition, since a margin part of an edge of the multilayer ceramic capacitor is formed to be thicker than a margin part of other regions of the multilayer ceramic capacitor, it is not easy to remove carbon therefrom at the time of calcining and sintering.
In order to solve the above-described problems, a method of forming the margin part on which the internal electrode is not formed in the previously manufactured ceramic multilayer body has been considered. However, such a method has a problem in that the manufactured ceramic multilayer body is vulnerable to impacts due to pores generated in a boundary surface of a cover region of the ceramic multilayer body and the margin part.
The related art document below discloses controlling porosity of a cover region of a ceramic multilayer body, but does not solve the above-described problems.